Australian Institute of Physics

South Australian Branch


presented by the Australian Institue of Physics and the

Centre for Subatomic Structure of Matter

Tuesday 25th March 7.30 pm

in the FLENTJE lecture theatre
(Plaza Building at the University of Adelaide)



Department of Physics
State University of New York
Stony Brook, New York


In the collapse of large stars, such as the progenitor of the last supernova explosion SN(1987)A, the core is imploded into high densities of several times nuclear matter density, the density in the center of nuclei. At these densities, the mass of the K-meson, which has a large mass of 495 MeV in free space, is brought down below the energy of the electrons on top of the Fermi sea. At this point, the electrons change into K-mesons (plus neutrinos which leave the core). The K-mesons are bosons, and go into a Bose condensate. The resulting equation of state is sufficiently soft that neutron stars of mass only about 1.5 Msolar (1.5 times the mass of the sun) can be stabilized. Arguments are given that the mass of the compact core in the last supernova explosion exceeded this value, and that a black hole was formed.


Professor Brown graduated from the University of Wisconsin in 1946 with a B.A. before going on to gain M.S. and Ph.D. degrees from Yale University in 1948 and 1950. In 1957, he was awarded a D.Sc. by the University of Birmingham. During a distinguished academic career, he has held professorships at the University of Birmingham, the Nordic Institute for Theoretical Atomic Physics (NORDITA, Copenhagen), Princeton University, and finally the State University of New York at Stony Brook, where he is currently Distinguished Professor of Physics. He has been active as a Founder and Editor of the journals "Physics Letters" and "Physics Reports" as well as editing "Nuclear Physics". Among his many awards are the Silver Medal of the University of Helsinki, the Haederspris from the Niels Bohr Institute, the Boris Pregel Award, New York Academy of Sciences, the Tom W. Bonner Prize in Nuclear Physics, and the John Price Wetherill Medal of the Franklin Institute. In addition, he has been made a Fellow of the Royal Danish Academy, the American Physical Society, the American Academy of Arts and Science, and received honorary doctorates from the Universities of Helsinki and Birmingham.